Statement —I: Electromagnets are made of soft iron.
Statement —II: Soft iron has lower permeability and high retentivity.
Choose the correct option related to statements.
Statement —II: Soft iron has lower permeability and high retentivity.
Choose the correct option related to statements.
- Statement — I is true but Statement — II is false
- Statement — I is false but Statement — II is true
- Statement — I is false and Statement — II is also false
- Statement —I is true and Statement —II is also true
The Correct Option is B
Solution and Explanation
Soft iron is used in electromagnets due to its high permeability, which allows magnetic lines of force to pass through it easily, and its low retentivity, which ensures it does not retain significant magnetism when the external field is removed.
Hence: Assertion \( A \) is correct because soft iron is the material of choice for electromagnets.
Reason \( R \) is correct because the properties of high permeability and low retentivity make soft iron ideal for electromagnets. Furthermore, \( R \) correctly explains \( A \).
Final Answer: Both statements are correct, and \( R \) is the correct explanation of \( A \): \[ \boxed{\text{(2) Both \( A \) and \( R \) are correct and \( R \) is the correct explanation of \( A \)}}. \]
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Concepts Used:
Magnetism & Matter
Magnets are used in many devices like electric bells, telephones, radio, loudspeakers, motors, fans, screwdrivers, lifting heavy iron loads, super-fast trains, especially in foreign countries, refrigerators, etc.
Magnetite is the world’s first magnet. This is also called a natural magnet. Though magnets occur naturally, we can also impart magnetic properties to a substance. It would be an artificial magnet in that case.
Read More: Magnetism and Matter
Some of the properties of the magnetic field lines are:
- The lines and continuous and outside the magnet, the field lines originate from the North pole and terminate at the South pole
- They form closed loops traversing inside the magnet.
- But here the lines seem to originate from the South pole and terminate at the North pole to form closed loops.
- More number of close lines indicate a stronger magnetic field
- The lines do not intersect each other
- The tangent drawn at the field line gives the direction of the field at that point.